Ayllón is a municipality located in the province of Segovia, Castile and León, Spain. According to the 2019 census, the municipality had a population of 1,196 inhabitants.
In 1411 a treaty, known as the Treaty of Ayllón, was signed between Portugal and Castile ending the wars of the Interregnum.
Wikipedia https://en.wikipedia.org/wiki/Ayllón
Coordinates 41°25'10.486" N -3°22'34.866" E